Study on effectiveness of systematic cardiotocography use in National Maternal and Child Health Center in Cambodia: A study protocol for an explanatory clinical trial

Abstract

Background and objective: An estimated 2 million stillbirths and 2.4 million neonatal deaths occur globally every year, and 98% of these deaths occur in low- and middle-income countries. The main causes of neonatal death are prematurity and intrapartum-related events, and half of stillbirths occur during labor. Although cardiotocography (CTG) is used to detect fetal hypoxia and acidosis in high-income countries, its effectiveness is not shown in resource-limited settings. This study aims to evaluate whether systematic CTG contributes to reducing fetal acidosis, stillbirths and neonatal deaths in a tertiary-level hospital in Cambodia. Methods: Participants will be pregnant women with moderate risk. The study employs pre- and post-comparison design, and consists of three phases: observation (pre), pre-intervention, and intervention (post). Standard care is applied during the observation phase. Training on CTG application using a local guideline is applied in the pre-intervention phase. Systematic CTG use and periodic supervision are key components of the intervention. The observation phase is between January and April 2023, and the intervention phase is between January and April 2024. Primary outcome is fetal acidosis, which manifests as a pH less than 7.20 in the umbilical arterial blood. The results in the observation and intervention phases will be compared using univariate and multivariate logistic regression analyses. Discussion: The novel idea of this study is the systematic use of CTG and the monitoring of hypoxic and acidotic states using blood gas analysis. It is expected that this study will contribute to show effectiveness of CTG use on reduction of fetal acidosis, and eventually on reduction of preventable child deaths in resource-limited settings. Clinical trial registration: UMIN000052815, UMIN Clinical Trials Registry (UMIN-CTR)